Human resources for health: overcoming the crisis

In this analysis of the global workforce, the Joint Learning Initiative-a consortium of more than 100 health leaders-proposes that mobilisation and strengthening of human resources for health, neglected yet critical, is central to combating health crises in some of the world's poorest countries and for building sustainable health systems in all countries. Nearly all countries are challenged by worker shortage, skill mix imbalance, maldistribution, negative work environment, and weak knowledge base. Especially in the poorest countries, the workforce is under assault by HIV/AIDS, out-migration, and inadequate investment. Effective country strategies should be backed by international reinforcement. Ultimately, the crisis in human resources is a shared problem requiring shared responsibility for cooperative action. Alliances for action are recommended to strengthen the performance of all existing actors while expanding space and energy for fresh actors.

Analysis of the degree of undertreatment of hyperlipidemia and congestive heart failure secondary to coronary artery disease

There is a lack of data evaluating the implementation of guidelines in the management of coronary artery disease (CAD) or congestive heart failure (CHF) in the outpatient setting. We analyzed an administrative data set from the Merck & Co. sponsored national Quality Assurance Program, a retrospective outpatient chart audit of 58,890 adult outpatients from 140 medical practices (80% cardiology only) in the USA with diagnoses of CAD and/or CHF identified from medical claims data. We determined the (1) frequency of lipid documentation and prescription of lipid-lowering agents in patients with CAD, (2) frequency of assessment of left ventricular function and prescription of an angiotensin-converting enzyme inhibitor in patients with CHF, and (3) predictors of medication prescription. Of the 48,586 patients with CAD, 44% had annual diagnostic testing of low-density lipoprotein cholesterol. Only 25% of these patients reached the target low-density lipoprotein cholesterol of < or = 100 mg/dl, and only 39% were taking lipid-lowering therapy, which was less among the elderly than in the younger patients. Of the 16,603 patients with CHF, 64% had diagnostic testing of left ventricular function, and 50% of patients were taking an angiotensin-converting enzyme inhibitor; 67% of patients received medication if they had documented systolic dysfunction. Significant predictors of medication prescription included diagnostic testing, younger age, history of myocardial infarction or coronary artery bypass grafting, hypertension, cardiology specialty, and geographic region. Thus, current practice patterns in the management of CAD and CHF are inadequate. Patient age, diagnostic testing, and practice environment influence medication prescription.

Gender, socioeconomic development and health-seeking behaviour in Bangladesh

In efforts to reduce gender and socioeconomic disparities in the health of populations, the provision of medical services alone is clearly inadequate. While socioeconomic development is assumed important in rectifying gender and socioeconomic inequities in health care access, service use and ultimately, outcomes, empirical evidence of its impact is limited. Using cross-sectional data from the BRAC-ICDDR,B Joint Research Project in Matlab, Bangladesh, this paper examines the impact of membership in BRAC's integrated Rural Development Programme (RDP) on gender equity and health-seeking behaviour. Differences in health care seeking are explored by comparing a sample of households who are BRAC members with a sample of BRAC-eligible non-members. Individuals from the BRAC member group report significantly less morbidity (15-day recall) than those from the non-member group, although no gender differences in the prevalence of self-reported morbidity are apparent in either group. Sick individuals from BRAC member households tend to seek care less frequently than non-members. When treatment is sought, BRAC members rely to a greater extent on home remedies, traditional care, and unqualified allopaths than non-member households. While reported treatment seeking from qualified allopaths is more prevalent in the BRAC group, non-members use the para-professional services of community health care workers almost twice as frequently. In both BRAC member and non-member groups, women suffering illness report seeking care significantly less often than men. The policy and programmatic implications of between group and gender differences in care seeking are discussed with reference to the literature.

In vitro sensitivity of the three mammalian collagenases to tetracycline inhibition: relationship to bone and cartilage degradation

There are at least nine tetracycline (TC) analogs (both antimicrobial and nonantimicrobial) with documented capacity to inhibit, both in vitro and in vivo, the connective tissue degrading activity of matrix metalloproteinases (MMPs). Of the three MMPs that can degrade native helical collagens, MMP-13 (initially identified as rat osteoblast and human breast cancer collagenase, and now known to also be expressed by human cartilage and bone cells) is the most sensitive to TC inhibition (IC50 values in vitro generally less than 1 microgram/mL); the TCs inhibit both the collagenolytic as well as the gelatinolytic activity of this enzyme. The IC50 for MMP-8 (neutrophil collagenase) in vitro ranges from 15 to 86 micrograms/mL depending on assay conditions and choice of TC, whereas inhibition of the fibroblast enzyme (MMP-1) generally requires levels in excess of 200 micrograms/mL (except for CMT-3). The TC compounds that are highly effective against MMP-13 in vitro are also highly inhibitory of glycosaminoglycan release from interleukin-1-stimulated cartilage explants in culture. The current data correlate well with: (i) literature values for TC inhibition of bone resorption by isolated osteoclasts; (ii) inhibition by TCs of avian tibial resorption in organ culture; and (iii) the dramatic ability of TCs to inhibit bone destruction in many rat models (rats have only MMP-8 and MMP-13, and no MMP-1). By carefully selecting a TC-based MMP inhibitor and controlling dosages, it should be possible to inhibit pathologically excessive MMP-8 and/or MMP-13 activity, especially that causing bone erosion, without affecting the constitutive levels of MMP-1 needed for tissue remodeling and normal host function; in this regard, three newly developed CMTs (especially CMT-8, and, to a lesser extent, CMT-3 and -7) appear to be most effective.

Community-based kangaroo mother care to prevent neonatal and infant mortality: a randomized, controlled cluster trial

OBJECTIVE

We adapted kangaroo mother care for immediate postnatal community-based application in rural Bangladesh, where the incidence of home delivery, low birth weight, and neonatal and infant mortality is high and neonatal intensive care is unavailable. This trial tested whether community-based kangaroo mother care reduces the overall neonatal mortality rate by 27.5%, infant mortality rate by 25%, and low birth weight neonatal mortality rate by 30%.

METHODS

Half of 42 unions in 2 Bangladesh divisions with the highest infant mortality rates were randomly assigned to community-based kangaroo mother care, and half were not. One village per union was randomly selected proportionate to union population size. A baseline survey of 39,888 eligible consenting women collected sociodemographic information. Community-based workers were taught to teach community-based kangaroo mother care to all expectant and postpartum women in the intervention villages. A total of 4165 live births were identified and enrolled. Newborns were followed for 30 to 45 days and infants were followed quarterly through their first birthday to record infant care, feeding, growth, health, and vital status.

RESULTS

Forty percent overall and approximately 65% of newborns who died were not weighed at birth, and missing birth weight was differential by study group. There was no difference in overall neonatal mortality rate or infant mortality rate. Except for care seeking, community-based kangaroo mother care behaviors were more common in the intervention than control group, but implementation was weak compared with the pilot study.

CONCLUSIONS

The extensive missing birth weight and its potential bias render the evidence insufficient to justify implementing community-based kangaroo mother care. Additional experimental research ensuring baseline comparability of mortality, adequate kangaroo mother care implementation, and birth weight assessment is necessary to clarify the effect of community-based kangaroo mother care on survival.

Activation of expression of genes coding for extracellular matrix proteins in Tat-producing glioblastoma cells

The Tat protein of human immunodeficiency virus type 1 has been increasingly implicated in directly contributing to the disease AIDS by altering the expression of strategic cellular genes. In this study we demonstrate that the presence of the human immunodeficiency virus type 1 regulatory protein Tat is associated with a significant induction in the expression of certain protein components of the extracellular matrix in glial-derived cells. Northern blot analysis reveals that in cells expressing Tat there is a marked elevation in the steady-state RNA levels for fibronectin and types I and III collagen. Metabolic labeling of the Tat-producing cells demonstrates that this induction is also reflected at the level of protein synthesis. Transient transfection experiments indicate that the presence of Tat results in increased transcription of fibronectin and alpha I type I collagen promoters. Possible mechanisms for this phenomenon and their significance with regard to AIDS are discussed.

TAR-independent transactivation by Tat in cells derived from the CNS: a novel mechanism of HIV-1 gene regulation

The Tat protein of human immunodeficiency virus type 1 (HIV-1) is essential for productive infection and is a potential target for antiviral therapy. Tat, a potent activator of HIV-1 gene expression, serves to greatly increase the rate of transcription directed by the viral promoter. This induction, which seems to be an important component in the progression of acquired immune deficiency syndrome (AIDS), may be due to increased transcriptional initiation, increased transcriptional elongation, or a combination of these processes. Much attention has been focused on the interaction of Tat with a specific RNA target termed TAR (transactivation responsive) which is present in the leader sequence of all HIV-1 mRNAs. This interaction is believed to be an important component of the mechanism of transactivation. In this report we demonstrate that in certain CNS-derived cells Tat is capable of activating HIV-1 through a TAR-independent pathway. A Tat-responsive element is found upstream within the viral promoter that in glial-derived cell lines allows transactivation in the absence of TAR. Deletion mapping and hybrid promoter constructs demonstrate that the newly identified Tat-responsive element corresponds to a sequence within the viral long terminal repeat (LTR) previously identified as the HIV-1 enhancer, or NF-kappa B domain. DNA band-shift analysis reveals NF-kappa B binding activity in glial cells that differs from that present in T lymphoid cells. Further, we observe that TAR-deleted mutants of HIV-1 demonstrate normal late gene expression in glial cells as evidenced by syncytia formation and production of viral p24 antigen.(ABSTRACT TRUNCATED AT 250 WORDS)

Changing health-seeking behaviour in Matlab, Bangladesh: do development interventions matter?

It is generally assumed that socioeconomic development interventions for the poor will enhance their material and social capacities to prevent ill health and to seek appropriate and timely care. Using cross-sectional data from surveys undertaken in 1995 and 1999 as part of the BRAC-ICDDR,B Joint Research Project in Matlab, Bangladesh, this paper explores patterns of health-seeking behaviour over time, with the hypothesis that exposure to integrated socioeconomic development activities will enhance gender equity in care-seeking and the use of qualified medical care. While there is tentative evidence of greater gender equity in treatment choice among households benefiting from development interventions, a preference for qualified medical care is not apparent. Findings reveal a striking and generalized rise in self-treatment over the 4-year period that is attributed to the economic repercussions of a major flood in 1998, and greater heath awareness due to the density of community health workers in Matlab. Also noteworthy is the substantial reliance on informal and often unqualified practitioners (over 20%) such as pharmacists and itinerant drug sellers. Factors associated with the type of health care sought were identified using logistic regression. Self-care is associated with female gender, the absence of low cost health services and illnesses of relatively short duration. Medical care, on the other hand, is positively predicted by male gender, geographic location, greater socioeconomic status and serious illness of long duration. The paper concludes by emphasizing the importance of enhancing local capacities to determine whether self-treatment is indicated, to self-treat appropriately, or in cases where health care is sought, to judge provider competence and evaluate whether treatment costs are justified. The provision of pharmaceutical training to the full spectrum of health care providers is also recommended.

Training traditional birth attendants in clean delivery does not prevent postpartum infection

OBJECTIVE

To compare the maternal outcome, in terms of postpartum infection, of deliveries conducted by trained traditional birth attendants (TBAs) with those conducted by untrained birth attendants.

METHODS

The study took place in a rural area of Bangladesh where a local NGO (BRAC) had previously undertaken TBA training. Demographic surveillance in the study site allowed the systematic identification of pregnant women. Pregnant women were recruited continuously over a period of 18 months. Data on the delivery circumstances were collected shortly after delivery while data on postpartum morbidity were collected prospectively at 2 and 6 weeks. All women with complete records who had delivered at home with a non-formal birth attendant (800) were included in the analysis. The intervention investigated was TBA training in hygienic delivery comprising the 'three cleans' (hand-washing with soap, clean cord care, clean surface). The key outcome measure was maternal postpartum genital tract infection diagnosed by a symptom complex of any two out of three symptoms: foul discharge, fever, lower abdominal pain.

RESULTS

Trained TBAs were significantly more likely to practice hygienic delivery than untrained TBAs (45.0 vs. 19.3%, p < 0.0001). However, no significant difference in levels of postpartum infection was found when deliveries by trained TBAs and untrained TBAs were compared. The practice of hygienic delivery itself also had no significant effect on postpartum infection. Logistic regression models confirmed that TBA training and hygienic delivery had no independent effect on postpartum outcome. Other factors, such as pre-existing infection, long labour and insertion of hands into the vagina were found to be highly significant.

CONCLUSIONS

Trained TBAs are more likely to practice hygienic delivery than those that are untrained. However, hygienic delivery practices do not prevent postpartum infection in this community. Training TBAs to wash their hands is not an effective strategy to prevent maternal postpartum infection. More rigorous evaluation is needed, not only of TBA training programmes as a whole, but also of the effectiveness of the individual components of the training.

Evidence that a sequence similar to TAR is important for induction of the JC virus late promoter by human immunodeficiency virus type 1 Tat

A specific RNA sequence located in the leader of all human immunodeficiency virus type 1 (HIV-1) mRNAs termed the transactivation response element, or TAR, is a primary target for induction of HIV-1 long terminal repeat activity by the HIV-1-derived trans-regulatory protein, Tat. Human neurotropic virus, JC virus (JCV), a causative agent of the degenerative demyelinating disease progressive multifocal leukoencephalopathy, contains sequences in the 5' end of the late RNA species with an extensive homology to HIV-1 TAR. In this study, we examined the possible role of the JCV-derived TAR-homologous sequence in Tat-mediated activation of the JCV late promoter (Tada et al., Proc. Natl. Acad. Sci. USA 87:3479-3483, 1990). Results from site-directed mutagenesis revealed that critical G residues required for the function of HIV-1 TAR that are conserved in the JCV TAR homolog play an important role in Tat activation of the JCV promoter. In addition, in vivo competition studies suggest that shared regulatory components mediate Tat activation of the JCV late and HIV-1 long terminal repeat promoters. Furthermore, we showed that the JCV-derived TAR sequence behaves in the same way as HIV-1 TAR in response to two distinct Tat mutants, one of which that has no ability to bind to HIV-1 TAR and another that lacks transcriptional activity on a responsive promoter. These results suggest that the TAR homolog of the JCV late promoter is responsive to HIV-1 Tat induction and thus may participate in the overall activation of the JCV late promoter mediated by this transactivation.

Spectroscopic behavior of Eu3+ in SnO2 for tunable red emission in solid state lighting devices

This paper reports a spectroscopic investigation of Eu³⁺ doped SnO₂ nanoparticles.

Effects of an organophosphate pesticide, quinalphos, on the hypothalamo-pituitary-gonadal axis in adult male rats

The effects of chronic sub-lethal doses (7-14 mg kg-1 a day for 15 days) of quinalphos were evaluated in adult male rats for changes in testicular morphology, circulatory concentrations of hormones (LH, FSH, prolactin and testosterone), activities of acetylcholinesterase (AChE) and angiotensin converting enzyme (ACE) as well as metabolism of biogenic amines (dopamine, noradrenaline and 5-hydroxytryptamine (5-HT)) in the hypothalamus and pituitary. Hormones were assayed by radioimmunoassay or chemiluminescent immunoassay (testosterone). The enzymes were estimated after spectrophotometry and the biogenic amines by HPLC-electrochemistry. Sub-lethal chronic administration of quinalphos resulted in: decreased testicular mass and AChE activity in central as well as peripheral organs; increased serum LH, FSH, prolactin and testosterone concentrations; decreased pituitary or increased testicular ACE activity; severe disruption of spermatogenesis with increasing doses of pesticide; and no significant effects on dopamine, noradrenaline or 5-HT concentrations in the hypothalamus or pituitary. Administration of oestradiol (50 micrograms per rat a day) during pesticide treatment resulted in: a significant decrease in the mass of the testis and accessory sex organs; decreases in serum LH, FSH, testosterone concentrations; an increase in prolactin concentration; and a decrease in dopamine or an increase in noradrenaline and 5-HT in the hypothalamus or pituitary. Oestradiol had a marked effect: in pesticide-treated animals, the pesticide effects were significantly reversed. This indicates that in pesticide toxicity, the hypothalamo-pituitary-gonadal axis is operational. Since many of the observed pesticide effects could be inhibited by oestradiol, it is suggested that the pesticide acts directly on the gonadotrophins. In conclusion, quinalphos decreases fertility in adult male rats by affecting the pituitary gonadotrophins.

Presynaptic adenosine A2 and N-methyl-D-aspartate receptors regulate dopamine synthesis in rat striatal synaptosomes

Dopamine synthesis rate and cyclic AMP concentration were measured in synaptosomes prepared from rat striatum. Dopamine synthesis rate was decreased by the addition of either adenosine deaminase or 8-phenyltheophylline, an adenosine receptor blocker, and was increased by the addition of 2-chloroadenosine. The addition of L-glutamate in the absence of adenosine deaminase decreased both dopamine synthesis rate and cyclic AMP concentration; in the presence of adenosine deaminase, glutamate had no effect on basal dopamine synthesis, but enhanced K(+)-stimulated synthesis. Both these effects of glutamate were abolished in Ca2(+)-free medium or in the presence of 2-amino-5-phosphonovalerate, an N-methyl-D-aspartate (NMDA) receptor blocker. In Mg2(+)-free medium with adenosine deaminase, glutamate enhanced both basal and K(+)-stimulated synthesis. These results suggest that dopaminergic terminals have A2 adenosine receptors, whose activation can stimulate dopamine synthesis by a cyclic AMP-dependent mechanism, and NMDA receptors, which modulate dopamine synthesis by a Ca2(+)-dependent mechanism.

Community health workers at the dawn of a new era: 11. CHWs leading the way to "Health for All"

BACKGROUND

This is the concluding paper of our 11-paper supplement, "Community health workers at the dawn of a new era".

METHODS

We relied on our collective experience, an extensive body of literature about community health workers (CHWs), and the other papers in this supplement to identify the most pressing challenges facing CHW programmes and approaches for strengthening CHW programmes.

RESULTS

CHWs are increasingly being recognized as a critical resource for achieving national and global health goals. These goals include achieving the health-related Sustainable Development Goals of Universal Health Coverage, ending preventable child and maternal deaths, and making a major contribution to the control of HIV, tuberculosis, malaria, and noncommunicable diseases. CHWs can also play a critical role in responding to current and future pandemics. For these reasons, we argue that CHWs are now at the dawn of a new era. While CHW programmes have long been an underfunded afterthought, they are now front and centre as the emerging foundation of health systems. Despite this increased attention, CHW programmes continue to face the same pressing challenges: inadequate financing, lack of supplies and commodities, low compensation of CHWs, and inadequate supervision. We outline approaches for strengthening CHW programmes, arguing that their enormous potential will only be realized when investment and health system support matches rhetoric. Rigorous monitoring, evaluation, and implementation research are also needed to enable CHW programmes to continuously improve their quality and effectiveness.

CONCLUSION

A marked increase in sustainable funding for CHW programmes is needed, and this will require increased domestic political support for prioritizing CHW programmes as economies grow and additional health-related funding becomes available. The paradigm shift called for here will be an important step in accelerating progress in achieving current global health goals and in reaching the goal of Health for All.

Hormonal influences on the level of testicular androgen binding activity: effect of FSH following hypophysectomy

Concentrations of high affinity (Ka equals 5.5 plus or minus 0.83 times 10-8M-1) androgen binding activity in carbonextracted rat testicular supernatants have been determined by Scatchard plot analysis under a variety of hormonal situations: (a) 0-90 days following hypophysectomy; (b) 0-60 days of daily injection of NIH-FSH-P1 (150 mug) beginning 1 day after hypophysectomy; and (c) 0-60 days of daily FSH treatment beginning 30 days after hypophysectomy. The high affinity binding component declined from 0.32 pmoles/mg protein intact adults to 0.28, 0.17, and less than 0.08 (limit of detectability) pmoles/mg protein at 11, 16 and 31 days, respectively. FSH treatment beginning immediately after surgery slowed this decline, giving values of 0.30, 0.17, and 0.12 pmoles/mg protein after 11, 29, and 54 days of treatment, respectively. Expressed as pmoles per testis this represented 96, 61, and 40% of the intact control level. Similar effects on the level of androgen binding protein (Rf 0.54) were measured by steady-state polyacrylamide gel electrophoresis (PAGE). The concentration in both testis and epididymis declined gradually to nondetectable levels by 30 days after surgery. FSH treatment for 11, 29, and 54 days, respectively, resulted in 0.37, 0.38, and 0.03 pmoles of sites/mg protein in testis compared to 0.34 in intact controls and 5.7, 2.6, and 0.2 pmoles/mg protein in epididymis compared to 2.8 in intact controls. Doses of 80, 150, and 300 mug FSH/rat/day for 3 days beginning 30 days after hypophysectomy when postmeiotic elements of the germinal epithelium had degenerated caused graded increases in both testicular and epididymal levels of androgen binding protein. Prolonged FSH treatment (150 mug) under these conditions resulted in an increase in binding activity to a level of 0.12, 0.19, 0.17, and 0.20 pmoles/mg protein after 3, 11, 25, and 56 days of treatment. On a per testis basis this represented less than 20% of intact control levels. PAGE estimates were comparable except at the long treatment intervals. These results indicate that FSH treatment influences the level of androgen binding protein in adult testis and epididymis. This may reflect a direct influence on synthesis, degradation, and transport and/or indirect effects on general maintenance and responsiveness of the pertinent cell types.

Beneficial effects of a woman-focused development programme on child survival: evidence from rural Bangladesh

This paper reports results from a prospective study of the impact of a woman-focused development programme on child survival in Matlab, a rural area of Bangladesh. The programme was targeted to households owning less than 50 decimals of land and members selling more than 100 days of labour for living in a year. Programme components included formation of women's groups for saving and credit, training on skill development, functional literacy including legal and social awareness, and technical and marketing support to projects undertaken with the loan money from the organization. A total of 13,549 children born alive during 1988-97 in the study area were included in the study. Hazards of mortality during pre- and post-intervention periods were compared among the programme participants and non-participants controlling the effects of other relevant variables. There has been a substantial reduction in mortality during the post-intervention period; however, the reduction was much greater for infants whose mothers participated in the development programme compared to infants of non-participant mothers from similar socioeconomic background. In a relative sense, there has been a 52% reduction of the pre-intervention level hazard of death of children during infancy of participant mothers compared to 31% reduction for the infants of non-participant mothers from similar socioeconomic background. There had also been a substantial reduction in hazard of death during childhood (1-4 year age group), however, the reduction was statistically similar for all groups of children irrespective of their mothers' participation in the development programmes.

Anaemia and iron deficiency during pregnancy in rural Bangladesh

OBJECTIVE

To study the prevalence of anaemia and its association with measures of iron deficiency (ID) among a group of pregnant women.

DESIGN

Cross-sectional survey.

SETTING

Pregnant women identified through house-to-house visits and participating in community-based antenatal care activities in a rural location of Mymensingh, Bangladesh.

SUBJECTS

The estimates are based on 214 reportedly healthy pregnant women in their second trimester. Information on socio-economic status and reproductive history were obtained through home visits and venous blood samples were collected at antenatal care centres. Haemoglobin concentration (Hb) was measured by HemoCue, serum ferritin (sFt) by radioimmunoassay and serum transferrin receptor (sTfR) by enzyme-linked immunosorbent assay methods. ID was defined as presence of either low sFt (<12 microg l(-1)) or high sTfR (>8.5 mg l(-1)).

RESULTS

The prevalence of anaemia (Hb <110 g l(-1)) was 50%, but severe anaemia (Hb <70 g l(-1)) was absent. Low sFt was observed in 42%, high sTfR in 25%, either low sFt or high TfR in 54% and both low sFt and high TfR in 13% of the pregnant women. Two out of three anaemic women had an indication of ID, which was present in 80% of women with moderate (Hb 70-99 g l(-1)) and 50% with mild (Hb 100-109 g l(-1)) anaemia. Four out of 10 non-anaemic women (Hb >/=110 g l(-1)) also had ID, but the prevalence was significantly lower than that observed in anaemic women (P=0.001).

CONCLUSIONS

Despite the high prevalence of anaemia, severe cases were absent. The prevalence of ID increased at lower Hb. However, an increased prevalence was also found among women in the highest category of Hb.

Penlight-cover test: a new bedside method to unmask nystagmus

BACKGROUND

Most patients with acute vestibular syndrome have vestibular neuritis or labyrinthitis. Some harbour strokes that can only be differentiated on the basis of subtle eye movement findings, including nystagmus. Peripheral nystagmus should be enhanced by removal of visual fixation. Current bedside methods for removing fixation require expensive equipment or technical skill not routinely available. We sought to test a new method for blocking fixation.

METHODS

Proof-of-concept study for a new bedside oculomotor diagnostic test using an established physiological measurement of eye movements (electro-oculography (EOG)) as the reference standard. We sampled unselected patients undergoing caloric testing (surrogate model for neuritis) in an academic vestibular clinic. During the brief (30-60 s) decay phase of caloric-induced peripheral vestibular nystagmus, we shone a penlight in the left eye while intermittently occluding the right. We assessed nystagmus intensity (slow-phase velocity) clinically in all subjects and quantified change in two exemplar cases.

RESULTS

Caloric responses frequently decayed before the test was complete, and artefacts rendered many EOGs uninterpretable during the short decay period. A clinically evident increase in nystagmus was seen 18 times in 10 patients and corroborated by EOG in 15. In quantified cases, slow-phase velocity increased as expected (mean change +42%) with fixation blocked.

CONCLUSION

The penlight-cover test could offer a low-cost, simple means of disrupting visual fixation in clinical settings where differentiating peripheral from central vestibular disorders is crucial, such as the emergency department. Prospective studies are needed to determine the test's utility for excluding dangerous central causes among patients with suspected peripheral lesions.

Inhibition of de novo synthesis of FSH by the Sertoli cell factor (SCF)

The effects of SCF, a substance produced by isolated rat Sertoli cells in culture, on the synthesis of FSH and LH were studied in vitro. Anterior pituitaries from adult male rats were organ-cultured 24-48h in the presence and absence of SCF in the culture medium. The incorporation of 3H-leucine into FSH and LH was determined following 6h incubation with this labelled precursor and immunoprecipitation with specific FSH or LH antibodies. Total FSH and LH were measured by radioimmunoassay. The results indicate that SCF can selectively reduce the incorporation of 3H-leucine into immunoprecipitable FSH without decreasing the incorporation into LH.